MLA

Stieglitz, Alfred, 1864-1946. Rodin, Auguste. Box 41, folder 989. 1911, n.d.. https://collections.library.yale.edu/catalog/11872487.

APA, 6th edition

Stieglitz, Alfred, 1864-1946. (["Box 41, folder 989"])(1911, n.d.)[Rodin, Auguste]. https://collections.library.yale.edu/catalog/11872487.